Linus Carl Pauling, the only person to win two unshared
Nobel Prizes, revolutionized the study of chemistry, helped
found the field of molecular biology, and made important
advances in medical research.

Linus Pauling was born 28 February 1901 in Portland,
Oregon, to a self-taught druggist, Herman Henry William
Pauling, and Isabelle (Belle) Pauling, the descendent of a
pioneer family. Linus received a strong blow at age nine
when his father died of a perforating ulcer, leaving a
wife, son, and two daughters on the edge of poverty. Belle
Pauling, stunned by her husband's sudden death and disabled
by pernicious anemia, spent her remaining years running a
boarding house on the outskirts of Portland. Linus withdrew
into books and hobbies. At age 14, a visit with a friend
who owned a toy chemistry set started Pauling on his life's
work. Entranced by the flames, smokes, odors, and by the
sight of mysterious changes in solutions and powders,
Pauling ran home and began assembling a rough "laboratory"
in a corner of his basement. Here he spent his teenage
years seeking order and solace in science.

During high school a sympathetic chemistry teacher
recognized Pauling's talent and provided special tutoring.
At age 16 Pauling dropped out to enroll at Oregon
Agricultural College (now Oregon State University),
intending to pursue a degree in chemical engineering.

Pauling quickly demonstrated that he knew more about
chemistry than many of his professors. While still an
undergraduate he was asked to teach chemistry courses in
the understaffed department, an experience that gave him
self-confidence--he became a great lecturer--and access to
current chemical journals. Teaching these courses also gave
Pauling the opportunity to meet--and later marry--Ava Helen
Miller, who was enrolled in his class as part of her home
economics coursework.

By the time he graduated as a chemical engineer in 1922 he
had set his sights on answering one of the most important
questions of chemistry: how did atoms bond together to form
molecules? In order to find out, he turned from chemical
engineering to chemical theory. He enrolled in the first
graduate program that offered adequate support, choosing a
fledgling Pasadena research school, the California
Institute of Technology, or Caltech. Pauling became one of
the first chemistry students in an outstanding doctoral
program designed and overseen by the famed chemist Arthur
Amos Noyes.

Noyes pointed Pauling in the direction of a new
experimental technique called x-ray crystallography, which
enabled scientists to learn about the sizes and
configurations of atoms within molecules and crystals.
Pauling earned his Ph.D. in 1925, and then spent 15 months
in Europe on a Guggenheim Fellowship, intending to study
the basics of atomic structure. His timing was propitious.
A group of European physicists, including Niels Bohr,
Werner Heisenberg, Wolfgang Pauli, Max Born, and Erwin
Schroedinger--all of whom Pauling met--were creating new
theories of atomic structure and behavior and fashioning a
powerful advance in science called quantum mechanics.
Pauling learned the difficult theory, as well as the
mathematics that underlay it, and was one of the first to
bring this important advance back to the United States.
Pauling returned to Caltech in 1927 as a faculty member,
and began to apply quantum mechanics to
problems of chemical structure and function. His 1939 work,
The Nature of the Chemical Bond,
encapsulated his ideas and
quickly became a standard work in the field.

At the age of 38, Pauling was a full professor and
head of the chemistry division at Caltech, the youngest
member ever elected to membership in the National Academy
of Sciences, and the father of four children (three sons,
Linus, Jr., Peter, and Crellin, and a daughter, Linda).

Pauling had started his structural studies by considering
inorganic molecules, but during the 1930s he shifted his
structural studies to large biomolecules, especially
proteins. His biomolecular research continued through World
War II, during which Pauling--an avid anti-Nazi--also
developed explosives and rocket propellants. He patented an
armor-piercing shell, invented an oxygen meter for
submarines, and was offered the chance to head the
chemistry program at the top-secret Manhattan Project--
which he turned down, not because he was averse to the idea
of the atomic bomb, but because it would mean uprooting his
family. After the war, his feelings towards weapons work
changed when, spurred by the pacifist activism of his wife,
Ava Helen, Pauling joined other scientists in calling for
civilian oversight and limitations on nuclear testing. He
met stiff opposition to his efforts in the charged days of
the budding Cold War.

Nonetheless, his scientific research was going well. In
1949, Pauling's team discovered the molecular basis of
sickle-cell anemia. He continued to work on the molecular
structure of amino acids and, in the early 1950s,
determined the large-scale structures of many proteins, the
so-called "alpha-helix." He also worked, though
unsuccessfully, on the structure of DNA. His many
achievements were crowned with the awarding of the Nobel
Prize in Chemistry in 1954, "for his research into the
nature of the chemical bond and its application to the
elucidation of the structure of complex substances."

After winning the Nobel Prize, Pauling focused his
attention on peace work, organizing scientists and speaking
out against nuclear testing and proliferation, often to
great criticism and at remarkable personal cost. His peace
activism work was capped in the fall of 1963 with the Nobel
Peace Prize for 1962 (a year in which no prize had been
awarded). The award was greeted with widespread criticism
in the press. The lukewarm congratulations of his home
institution, Caltech, led to his painful resignation from
the school that had been his academic home for more than 40
years.

Pauling spent the next decade as an academic nomad, working
at different think tanks and universities. For over twenty
years, between 1973 and 1994, Pauling's research focused on
a field he termed "orthomolecular medicine," the concept
that optimal health could result from ensuring that the right
molecules were present in the right amount in the body. He
viewed vitamin C as one of the most important of these
molecules, oversaw a number of investigations into its
effects on diseases, and encouraged the ingestion of daily
amounts many times greater than the accepted minimum daily
requirement. Many physicians attacked his approach; the
medical community criticized his decision to publish a
popular book on the subject without prior peer-reviewed
scientific publication; and many thought his claims
unsubstantiated. Pauling fought back with typical
determination. In 1973 he co-founded a
California research institute devoted to the study of the
health effects of vitamin C and other nutrients. He
conducted research there until his death from cancer in
1994, at age 93.

Pauling's long career path led from physics to chemistry to
biology to medicine. At every turn he was eager to jump
disciplinary fences and explore new territory at the
borders. He was attacked for his political beliefs and for
going outside of accepted channels in making his results
widely known. Nevertheless, in the course of his long
career he wrote more than five hundred papers and eleven
books, won every important prize awarded in his field, and
can be considered the most significant chemist of his time.

1933 --Elected a member of the National Academy of Sciences, and at that time, the youngest person so elected

1935 --Publishes Introduction to Quantum Mechanics, with Applications to Chemistry, co-written with E. Bright Wilson, an expansion
of the notes Pauling used in preparing a Caltech course on wave mechanics

1936-54 --Research on protein structure

1937 --Chairman of the Division of Chemistry and Director of the Gates Laboratory, California Institute of Technology

1937-38 --George Fisher Baker Lecturer in Chemistry at Cornell University

1939 --Publishes The Nature of the Chemical Bond and The Structure of Molecules and Crystals: An Introduction to Modern
Structural Chemistry, Pauling's most important and path-breaking work

1940-43 --Chairman of the Chemistry Section, National Academy of Science

1948 --Receives Presidential Medal for Merit; Eastman Professor, Balliol College of Oxford University; Scott Lecturer at Cambridge
University; honorary doctorates from Oxford University and the University of Paris

1949 --President, American Chemical Society; publishes research on sickle-cell anemia

1958 --Presents petition to halt bomb testing, signed by thousands of scientists, to the United Nations; publishes No More War!;
resigns from Caltech administrative positions

1960 --Subpoenaed to testify about his anti-nuclear testing petition before the United States Senate Subcommittee on Internal Security;
appears twice and is threatened with contempt when he refuses to name those who helped him circulate the petition; following
publicity about the case, no contempt citation is issued